Dai, if that's the case you'd see the signals firing the injectors? Or would the trickle of fuel come from somewhere else? Pardon my ignorance here, this is not a side of things I've delved into before.

Pull the rail up and switch the ignition on. Let the system prime and you'll see if you are leaking fuel from the injectors. 3 of the 5 on mine are weeping.

Now there's a level headed suggestion! Thanks for that monkeh, sounds like just the thing and easier too.

Digging around thsi guy has a similiar issue:

http://www.volvoforums.org.uk/showthread.php?t=156686

Sounds like we're on the right track here
 

Sounds like we're on the right track here. Never pulled a rail, but doesn't sound hard. The fault costs me £150 a year.

My worry, I've just looked on ebay and petrol injectors are £60-70 a go and if its likely we've all got as monkeh says...

we're almost better to live with it. For me it'll take 2 years to pay for itself, excluding the hassle.

But 1 x nozzles only are £19 each.

But I am curious. I'll try it this weekend if I can. If I have 1 x injector weeping, and I can pick up a used set of 5 for near nowt (one or two are likely to weep too) it is worth doing.

I like Dai's suggestion to pull the pump fuse to see what it does, but if cooling is required, this could be risky. It could feck it right up. I'm persisted off, I liked my £15.00 shut off valve idea.

I have to look out for a set pretty sharp, Im sure that the leaky injectors are causing a poor start after being sat for a few hours. If the car isnt started for a few days, it fires right up.
Ebay sellers know what they are doing by pricing up injectors that high.

If Anyone has an 850 T5, I have a set of injectors that I bought by mistake. They overfuel my NA and arent suitable for it.

More digging....
 

Seems we all have an injector problem...

http://www.volvoforums.org.uk/showthread.php?t=49683

Monkeh: Can I ask what are you're running. Reason I ask is I'm trying to work out waht I should be buying, I run a 1999 V70 Bifuel, do you know which injectors I should be looking at. If I buy used, are the turbo modles running the same part?

I could strip it down to see, but don't want to do that unless I have a repalcemtn set to hand.

There is an argument for gettting your existing set cleaned it seems.

Reading more of this thread, I am now wondering if Volvo designed the Bi-fuels to run on a trickle of petrol. Would volvo know the answer to this question if asked? I somehow manage to use 3 or 4 gallons a month of petrol.

I have a 1998 v70 2.4 non turbo with LPG. I have tried to clean them, actually removing them and using a low current 12v supply to switch the injectors, I ran carb and injector cleaner through them, still no different, Even backflushing them, So I guess I need new injectors. I bought some off a forum member when I thought all I needed was 'Orange injectors' thinking they were a fixed flow rate...
The t5 injectors I put on supply more fuel at higher revs and it bogged the car down and lost power. So the leaky injectors are back on and the performance is better, Albeit Im having to top the petrol up every so often.